α1-blocker tamsulosin as initial treatment for patients with benign prostatic hyperplasia: 5-year outcome analysis of a prospective multicenter study

Objective To comprehensively analyze the 5‐year outcomes of tamsulosin treatment for patients with benign prostatic hyperplasia. Methods Tamsulosin (0.2 mg/day) was given to 112 patients who had International Prostate Symptom Scores ≥8. They were prospectively followed for 5 years with periodic evaluation. If tamsulosin had to be discontinued, the reason was determined. Treatment failure was considered in the case of disease progression (postvoid residual urine volume ≥200 mL, acute urinary retention, febrile urinary tract infection or hydronephrosis as a result of bladder outlet obstruction), conversion to other α1‐blockers or need for surgery. An intention‐to‐treat analysis was carried out. Results A total of 34 patients (30.4%) continued the same medication for the overall study period, whereas 78 patients (69.6%) discontinued the medication. International Prostate Symptom Scores, Benign Prostatic Hyperplasia Problem Index and Quality of Life Index were significantly improved over the 5‐year period. Treatment failure was observed in 21 patients (18.8%). Baseline prostate volume and postvoid residual urine volume were independent factors to predicting treatment failure. A total of 21 patients (18.8%) discontinued tamsulosin because of an improvement of symptoms. They were younger and had lower prostate‐specific antigen levels than the remaining 91 patients. Their symptoms were stable even 1 year after termination of therapy. Conclusions Long‐term efficacy of tamsulosin was observed, although only a small portion of patients continued the treatment. α1‐blocker monotherapy might be not appropriate for achieving a good long‐term outcome in patients with a large prostate volume and a large amount of postvoid residual urine volume. Persistent improvement of symptoms, even after termination of tamsulosin, was observed in young patients with low prostate‐specific antigen levels.